2 * Copyright (c) 2011, 2012 Nicira Networks.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
21 #include "byte-order.h"
22 #include "dynamic-string.h"
23 #include "meta-flow.h"
25 #include "ofp-errors.h"
28 #include "openflow/openflow.h"
29 #include "unaligned.h"
32 get_be16(const void **pp)
34 const ovs_be16 *p = *pp;
41 get_be32(const void **pp)
43 const ovs_be32 *p = *pp;
44 ovs_be32 value = get_unaligned_be32(p);
50 get_bits(int n_bits, const void **p)
52 int n_segs = DIV_ROUND_UP(n_bits, 16);
56 while (n_segs-- > 0) {
57 value = (value << 16) | ntohs(get_be16(p));
63 get_subfield(int n_bits, const void **p, struct mf_subfield *sf)
65 sf->field = mf_from_nxm_header(ntohl(get_be32(p)));
66 sf->ofs = ntohs(get_be16(p));
71 learn_min_len(uint16_t header)
73 int n_bits = header & NX_LEARN_N_BITS_MASK;
74 int src_type = header & NX_LEARN_SRC_MASK;
75 int dst_type = header & NX_LEARN_DST_MASK;
79 if (src_type == NX_LEARN_SRC_FIELD) {
80 min_len += sizeof(ovs_be32); /* src_field */
81 min_len += sizeof(ovs_be16); /* src_ofs */
83 min_len += DIV_ROUND_UP(n_bits, 16);
85 if (dst_type == NX_LEARN_DST_MATCH ||
86 dst_type == NX_LEARN_DST_LOAD) {
87 min_len += sizeof(ovs_be32); /* dst_field */
88 min_len += sizeof(ovs_be16); /* dst_ofs */
94 learn_check_header(uint16_t header, size_t len)
96 int src_type = header & NX_LEARN_SRC_MASK;
97 int dst_type = header & NX_LEARN_DST_MASK;
99 /* Check for valid src and dst type combination. */
100 if (dst_type == NX_LEARN_DST_MATCH ||
101 dst_type == NX_LEARN_DST_LOAD ||
102 (dst_type == NX_LEARN_DST_OUTPUT &&
103 src_type == NX_LEARN_SRC_FIELD)) {
106 return OFPERR_OFPBAC_BAD_ARGUMENT;
109 /* Check that the arguments don't overrun the end of the action. */
110 if (len < learn_min_len(header)) {
111 return OFPERR_OFPBAC_BAD_LEN;
117 /* Checks that 'learn' (which must be at least 'sizeof *learn' bytes long) is a
118 * valid action on 'flow'. */
120 learn_check(const struct nx_action_learn *learn, const struct flow *flow)
122 struct cls_rule rule;
125 cls_rule_init_catchall(&rule, 0);
127 if (learn->flags & ~htons(OFPFF_SEND_FLOW_REM)
129 || learn->table_id == 0xff) {
130 return OFPERR_OFPBAC_BAD_ARGUMENT;
133 end = (char *) learn + ntohs(learn->len);
134 for (p = learn + 1; p != end; ) {
135 uint16_t header = ntohs(get_be16(&p));
136 int n_bits = header & NX_LEARN_N_BITS_MASK;
137 int src_type = header & NX_LEARN_SRC_MASK;
138 int dst_type = header & NX_LEARN_DST_MASK;
147 error = learn_check_header(header, (char *) end - (char *) p);
152 /* Check the source. */
153 if (src_type == NX_LEARN_SRC_FIELD) {
154 struct mf_subfield src;
156 get_subfield(n_bits, &p, &src);
157 error = mf_check_src(&src, flow);
163 value = get_bits(n_bits, &p);
166 /* Check the destination. */
167 if (dst_type == NX_LEARN_DST_MATCH || dst_type == NX_LEARN_DST_LOAD) {
168 struct mf_subfield dst;
170 get_subfield(n_bits, &p, &dst);
171 error = (dst_type == NX_LEARN_DST_LOAD
172 ? mf_check_dst(&dst, &rule.flow)
173 : mf_check_src(&dst, &rule.flow));
178 if (dst_type == NX_LEARN_DST_MATCH
179 && src_type == NX_LEARN_SRC_IMMEDIATE) {
181 mf_set_subfield(&dst, value, &rule);
183 /* We're only setting subfields to allow us to check
184 * prerequisites. No prerequisite depends on the value of
185 * a field that is wider than 64 bits. So just skip
186 * setting it entirely. */
191 if (!is_all_zeros(p, (char *) end - (char *) p)) {
192 return OFPERR_OFPBAC_BAD_ARGUMENT;
199 learn_execute(const struct nx_action_learn *learn, const struct flow *flow,
200 struct ofputil_flow_mod *fm)
203 struct ofpbuf actions;
205 cls_rule_init_catchall(&fm->cr, ntohs(learn->priority));
206 fm->cookie = learn->cookie;
207 fm->cookie_mask = htonll(UINT64_MAX);
208 fm->table_id = learn->table_id;
209 fm->command = OFPFC_MODIFY_STRICT;
210 fm->idle_timeout = ntohs(learn->idle_timeout);
211 fm->hard_timeout = ntohs(learn->hard_timeout);
212 fm->buffer_id = UINT32_MAX;
213 fm->out_port = OFPP_NONE;
214 fm->flags = ntohs(learn->flags) & OFPFF_SEND_FLOW_REM;
218 ofpbuf_init(&actions, 64);
220 if (learn->fin_idle_timeout || learn->fin_hard_timeout) {
221 struct nx_action_fin_timeout *naft;
223 naft = ofputil_put_NXAST_FIN_TIMEOUT(&actions);
224 naft->fin_idle_timeout = learn->fin_idle_timeout;
225 naft->fin_hard_timeout = learn->fin_hard_timeout;
228 for (p = learn + 1, end = (char *) learn + ntohs(learn->len); p != end; ) {
229 uint16_t header = ntohs(get_be16(&p));
230 int n_bits = header & NX_LEARN_N_BITS_MASK;
231 int src_type = header & NX_LEARN_SRC_MASK;
232 int dst_type = header & NX_LEARN_DST_MASK;
233 union mf_subvalue value;
235 struct mf_subfield dst;
242 if (src_type == NX_LEARN_SRC_FIELD) {
243 struct mf_subfield src;
245 get_subfield(n_bits, &p, &src);
246 mf_read_subfield(&src, flow, &value);
248 int p_bytes = 2 * DIV_ROUND_UP(n_bits, 16);
250 memset(&value, 0, sizeof value);
251 bitwise_copy(p, p_bytes, 0,
252 &value, sizeof value, 0,
254 p = (const uint8_t *) p + p_bytes;
258 case NX_LEARN_DST_MATCH:
259 get_subfield(n_bits, &p, &dst);
260 mf_write_subfield(&dst, &value, &fm->cr);
263 case NX_LEARN_DST_LOAD:
264 get_subfield(n_bits, &p, &dst);
265 for (ofs = 0; ofs < n_bits; ofs += chunk) {
266 struct nx_action_reg_load *load;
268 chunk = MIN(n_bits - ofs, 64);
270 load = ofputil_put_NXAST_REG_LOAD(&actions);
271 load->ofs_nbits = nxm_encode_ofs_nbits(dst.ofs + ofs, chunk);
272 load->dst = htonl(dst.field->nxm_header);
273 bitwise_copy(&value, sizeof value, ofs,
274 &load->value, sizeof load->value, 0,
279 case NX_LEARN_DST_OUTPUT:
280 if (n_bits <= 16 || is_all_zeros(value.u8, sizeof value - 2)) {
281 ofputil_put_OFPAT10_OUTPUT(&actions)->port = value.be16[7];
287 fm->actions = ofpbuf_steal_data(&actions);
288 fm->n_actions = actions.size / sizeof(struct ofp_action_header);
292 put_be16(struct ofpbuf *b, ovs_be16 x)
294 ofpbuf_put(b, &x, sizeof x);
298 put_be32(struct ofpbuf *b, ovs_be32 x)
300 ofpbuf_put(b, &x, sizeof x);
304 put_u16(struct ofpbuf *b, uint16_t x)
306 put_be16(b, htons(x));
310 put_u32(struct ofpbuf *b, uint32_t x)
312 put_be32(b, htonl(x));
319 struct mf_subfield src;
320 uint8_t src_imm[sizeof(union mf_value)];
323 struct mf_subfield dst;
327 learn_parse_spec(const char *orig, char *name, char *value,
328 struct learn_spec *spec)
330 memset(spec, 0, sizeof *spec);
331 if (mf_from_name(name)) {
332 const struct mf_field *dst = mf_from_name(name);
336 error = mf_parse_value(dst, value, &imm);
338 ovs_fatal(0, "%s", error);
341 spec->n_bits = dst->n_bits;
342 spec->src_type = NX_LEARN_SRC_IMMEDIATE;
343 memcpy(spec->src_imm, &imm, dst->n_bytes);
344 spec->dst_type = NX_LEARN_DST_MATCH;
345 spec->dst.field = dst;
347 spec->dst.n_bits = dst->n_bits;
348 } else if (strchr(name, '[')) {
349 /* Parse destination and check prerequisites. */
350 if (mf_parse_subfield(&spec->dst, name)[0] != '\0') {
351 ovs_fatal(0, "%s: syntax error after NXM field name `%s'",
355 /* Parse source and check prerequisites. */
356 if (value[0] != '\0') {
357 if (mf_parse_subfield(&spec->src, value)[0] != '\0') {
358 ovs_fatal(0, "%s: syntax error after NXM field name `%s'",
361 if (spec->src.n_bits != spec->dst.n_bits) {
362 ovs_fatal(0, "%s: bit widths of %s (%u) and %s (%u) differ",
363 orig, name, spec->src.n_bits, value,
367 spec->src = spec->dst;
370 spec->n_bits = spec->src.n_bits;
371 spec->src_type = NX_LEARN_SRC_FIELD;
372 spec->dst_type = NX_LEARN_DST_MATCH;
373 } else if (!strcmp(name, "load")) {
374 if (value[strcspn(value, "[-")] == '-') {
375 struct nx_action_reg_load load;
376 int nbits, imm_bytes;
380 nxm_parse_reg_load(&load, value);
381 nbits = nxm_decode_n_bits(load.ofs_nbits);
382 imm_bytes = DIV_ROUND_UP(nbits, 8);
383 imm = ntohll(load.value);
385 spec->n_bits = nbits;
386 spec->src_type = NX_LEARN_SRC_IMMEDIATE;
387 for (i = 0; i < imm_bytes; i++) {
388 spec->src_imm[i] = imm >> ((imm_bytes - i - 1) * 8);
390 spec->dst_type = NX_LEARN_DST_LOAD;
391 nxm_decode(&spec->dst, load.dst, load.ofs_nbits);
393 struct nx_action_reg_move move;
395 nxm_parse_reg_move(&move, value);
397 spec->n_bits = ntohs(move.n_bits);
398 spec->src_type = NX_LEARN_SRC_FIELD;
399 nxm_decode_discrete(&spec->src,
400 move.src, move.src_ofs, move.n_bits);
401 spec->dst_type = NX_LEARN_DST_LOAD;
402 nxm_decode_discrete(&spec->dst,
403 move.dst, move.dst_ofs, move.n_bits);
405 } else if (!strcmp(name, "output")) {
406 if (mf_parse_subfield(&spec->src, value)[0] != '\0') {
407 ovs_fatal(0, "%s: syntax error after NXM field name `%s'",
411 spec->n_bits = spec->src.n_bits;
412 spec->src_type = NX_LEARN_SRC_FIELD;
413 spec->dst_type = NX_LEARN_DST_OUTPUT;
415 ovs_fatal(0, "%s: unknown keyword %s", orig, name);
419 /* Parses 'arg' as a set of arguments to the "learn" action and appends a
420 * matching NXAST_LEARN action to 'b'. The format parsed is described in
423 * Prints an error on stderr and aborts the program if 'arg' syntax is invalid.
425 * If 'flow' is nonnull, then it should be the flow from a cls_rule that is
426 * the matching rule for the learning action. This helps to better validate
427 * the action's arguments.
431 learn_parse(struct ofpbuf *b, char *arg, const struct flow *flow)
433 char *orig = xstrdup(arg);
439 struct nx_action_learn *learn;
440 struct cls_rule rule;
443 learn = ofputil_put_NXAST_LEARN(b);
444 learn->idle_timeout = htons(OFP_FLOW_PERMANENT);
445 learn->hard_timeout = htons(OFP_FLOW_PERMANENT);
446 learn->priority = htons(OFP_DEFAULT_PRIORITY);
447 learn->cookie = htonll(0);
448 learn->flags = htons(0);
451 cls_rule_init_catchall(&rule, 0);
452 while (ofputil_parse_key_value(&arg, &name, &value)) {
453 learn = ofpbuf_at_assert(b, learn_ofs, sizeof *learn);
454 if (!strcmp(name, "table")) {
455 learn->table_id = atoi(value);
456 if (learn->table_id == 255) {
457 ovs_fatal(0, "%s: table id 255 not valid for `learn' action",
460 } else if (!strcmp(name, "priority")) {
461 learn->priority = htons(atoi(value));
462 } else if (!strcmp(name, "idle_timeout")) {
463 learn->idle_timeout = htons(atoi(value));
464 } else if (!strcmp(name, "hard_timeout")) {
465 learn->hard_timeout = htons(atoi(value));
466 } else if (!strcmp(name, "fin_idle_timeout")) {
467 learn->fin_idle_timeout = htons(atoi(value));
468 } else if (!strcmp(name, "fin_hard_timeout")) {
469 learn->fin_hard_timeout = htons(atoi(value));
470 } else if (!strcmp(name, "cookie")) {
471 learn->cookie = htonll(strtoull(value, NULL, 0));
473 struct learn_spec spec;
475 learn_parse_spec(orig, name, value, &spec);
477 /* Check prerequisites. */
478 if (spec.src_type == NX_LEARN_SRC_FIELD
479 && flow && !mf_are_prereqs_ok(spec.src.field, flow)) {
480 ovs_fatal(0, "%s: cannot specify source field %s because "
481 "prerequisites are not satisfied",
482 orig, spec.src.field->name);
484 if ((spec.dst_type == NX_LEARN_DST_MATCH
485 || spec.dst_type == NX_LEARN_DST_LOAD)
486 && !mf_are_prereqs_ok(spec.dst.field, &rule.flow)) {
487 ovs_fatal(0, "%s: cannot specify destination field %s because "
488 "prerequisites are not satisfied",
489 orig, spec.dst.field->name);
492 /* Update 'rule' to allow for satisfying destination
494 if (spec.src_type == NX_LEARN_SRC_IMMEDIATE
495 && spec.dst_type == NX_LEARN_DST_MATCH
497 && spec.n_bits == spec.dst.field->n_bytes * 8) {
500 memcpy(&imm, spec.src_imm, spec.dst.field->n_bytes);
501 mf_set_value(spec.dst.field, &imm, &rule);
504 /* Output the flow_mod_spec. */
505 put_u16(b, spec.n_bits | spec.src_type | spec.dst_type);
506 if (spec.src_type == NX_LEARN_SRC_IMMEDIATE) {
507 int n_bytes = DIV_ROUND_UP(spec.n_bits, 8);
509 ofpbuf_put_zeros(b, 1);
511 ofpbuf_put(b, spec.src_imm, n_bytes);
513 put_u32(b, spec.src.field->nxm_header);
514 put_u16(b, spec.src.ofs);
516 if (spec.dst_type == NX_LEARN_DST_MATCH ||
517 spec.dst_type == NX_LEARN_DST_LOAD) {
518 put_u32(b, spec.dst.field->nxm_header);
519 put_u16(b, spec.dst.ofs);
521 assert(spec.dst_type == NX_LEARN_DST_OUTPUT);
528 len = b->size - learn_ofs;
530 ofpbuf_put_zeros(b, 8 - len % 8);
533 learn = ofpbuf_at_assert(b, learn_ofs, sizeof *learn);
534 learn->len = htons(b->size - learn_ofs);
536 /* In theory the above should have caught any errors, but... */
538 error = learn_check(learn, flow);
540 ovs_fatal(0, "%s: %s", orig, ofperr_to_string(error));
547 learn_format(const struct nx_action_learn *learn, struct ds *s)
549 struct cls_rule rule;
552 cls_rule_init_catchall(&rule, 0);
554 ds_put_format(s, "learn(table=%"PRIu8, learn->table_id);
555 if (learn->idle_timeout != htons(OFP_FLOW_PERMANENT)) {
556 ds_put_format(s, ",idle_timeout=%"PRIu16, ntohs(learn->idle_timeout));
558 if (learn->hard_timeout != htons(OFP_FLOW_PERMANENT)) {
559 ds_put_format(s, ",hard_timeout=%"PRIu16, ntohs(learn->hard_timeout));
561 if (learn->fin_idle_timeout) {
562 ds_put_format(s, ",fin_idle_timeout=%"PRIu16,
563 ntohs(learn->fin_idle_timeout));
565 if (learn->fin_hard_timeout) {
566 ds_put_format(s, ",fin_hard_timeout=%"PRIu16,
567 ntohs(learn->fin_hard_timeout));
569 if (learn->priority != htons(OFP_DEFAULT_PRIORITY)) {
570 ds_put_format(s, ",priority=%"PRIu16, ntohs(learn->priority));
572 if (learn->flags & htons(OFPFF_SEND_FLOW_REM)) {
573 ds_put_cstr(s, ",OFPFF_SEND_FLOW_REM");
575 if (learn->flags & htons(~OFPFF_SEND_FLOW_REM)) {
576 ds_put_format(s, ",***flags=%"PRIu16"***",
577 ntohs(learn->flags) & ~OFPFF_SEND_FLOW_REM);
579 if (learn->cookie != htonll(0)) {
580 ds_put_format(s, ",cookie=0x%"PRIx64, ntohll(learn->cookie));
582 if (learn->pad != 0) {
583 ds_put_cstr(s, ",***nonzero pad***");
586 end = (char *) learn + ntohs(learn->len);
587 for (p = learn + 1; p != end; ) {
588 uint16_t header = ntohs(get_be16(&p));
589 int n_bits = header & NX_LEARN_N_BITS_MASK;
591 int src_type = header & NX_LEARN_SRC_MASK;
592 struct mf_subfield src;
593 const uint8_t *src_value;
596 int dst_type = header & NX_LEARN_DST_MASK;
597 struct mf_subfield dst;
606 error = learn_check_header(header, (char *) end - (char *) p);
607 if (error == OFPERR_OFPBAC_BAD_ARGUMENT) {
608 ds_put_format(s, ",***bad flow_mod_spec header %"PRIx16"***)",
611 } else if (error == OFPERR_OFPBAC_BAD_LEN) {
612 ds_put_format(s, ",***flow_mod_spec at offset %td is %u bytes "
613 "long but only %td bytes are left***)",
614 (char *) p - (char *) (learn + 1) - 2,
615 learn_min_len(header) + 2,
616 (char *) end - (char *) p + 2);
621 /* Get the source. */
622 if (src_type == NX_LEARN_SRC_FIELD) {
623 get_subfield(n_bits, &p, &src);
630 src_value_bytes = 2 * DIV_ROUND_UP(n_bits, 16);
632 p = (const void *) ((const uint8_t *) p + src_value_bytes);
635 /* Get the destination. */
636 if (dst_type == NX_LEARN_DST_MATCH || dst_type == NX_LEARN_DST_LOAD) {
637 get_subfield(n_bits, &p, &dst);
646 switch (src_type | dst_type) {
647 case NX_LEARN_SRC_IMMEDIATE | NX_LEARN_DST_MATCH:
648 if (dst.field && dst.ofs == 0 && n_bits == dst.field->n_bits) {
649 union mf_value value;
650 uint8_t *bytes = (uint8_t *) &value;
652 if (src_value_bytes > dst.field->n_bytes) {
653 /* The destination field is an odd number of bytes, which
654 * got rounded up to a multiple of 2 to be put into the
655 * learning action. Skip over the leading byte, which
656 * should be zero anyway. Otherwise the memcpy() below
657 * will overrun the start of 'value'. */
658 int diff = src_value_bytes - dst.field->n_bytes;
660 src_value_bytes -= diff;
663 memset(&value, 0, sizeof value);
664 memcpy(&bytes[dst.field->n_bytes - src_value_bytes],
665 src_value, src_value_bytes);
666 ds_put_format(s, "%s=", dst.field->name);
667 mf_format(dst.field, &value, NULL, s);
669 mf_format_subfield(&dst, s);
670 ds_put_cstr(s, "=0x");
671 for (i = 0; i < src_value_bytes; i++) {
672 ds_put_format(s, "%02"PRIx8, src_value[i]);
677 case NX_LEARN_SRC_FIELD | NX_LEARN_DST_MATCH:
678 mf_format_subfield(&dst, s);
679 if (src.field != dst.field || src.ofs != dst.ofs) {
681 mf_format_subfield(&src, s);
685 case NX_LEARN_SRC_IMMEDIATE | NX_LEARN_DST_LOAD:
686 ds_put_cstr(s, "load:0x");
687 for (i = 0; i < src_value_bytes; i++) {
688 ds_put_format(s, "%02"PRIx8, src_value[i]);
690 ds_put_cstr(s, "->");
691 mf_format_subfield(&dst, s);
694 case NX_LEARN_SRC_FIELD | NX_LEARN_DST_LOAD:
695 ds_put_cstr(s, "load:");
696 mf_format_subfield(&src, s);
697 ds_put_cstr(s, "->");
698 mf_format_subfield(&dst, s);
701 case NX_LEARN_SRC_FIELD | NX_LEARN_DST_OUTPUT:
702 ds_put_cstr(s, "output:");
703 mf_format_subfield(&src, s);
707 if (!is_all_zeros(p, (char *) end - (char *) p)) {
708 ds_put_cstr(s, ",***nonzero trailer***");